A transport interface for time division frames, in particular SDH frames transmitted between telecommunications network nodes according to a specified transport protocol, said nodes comprising first circuit means (SM) for processing said time division frames (TRM, TRM2) according to said specified transport protocol, and second circuit means (FP) apt to exchange second information streams (FDS) with said first circuit means (SM) through said transport interface (STI). According to the invention, said second information streams (FDS), exchanged by the transport interface (STI) with the first circuit means (SM) and with the second circuit means (FP), are simplified with respect to said time division frames (TRM1, TRM2) received from said node, in particular are composed by a data stream (BD, T_BD, R_BD) sent in a co-directional way and by an address information (EAR, T_EAR, R_EAR) sent by the transport interface (STI).